Comparative anatomy of the urological systems Flashcards
1
Q
what is the ‘elimination’ function of urological systems?
A
elimination of waste products
2
Q
what are the regulation functions of the urological systems?
A
regulation of body fluid and blood pH (acid/base balance)
AND
regulation of electrolyte balance (Na+, K+, Cl-)
3
Q
what are the production functions of the urological systems?
A
production of hormones; renin and erythropoietin
produce glucose from substances other than carbs
VitD production
4
Q
organs of the urinary system?
A
kidneys
ureter
bladder
urethra
5
Q
function of urethra?
A
directs urine out
6
Q
function of kidneys?
A
produce urine
7
Q
function of ureter?
A
directs urine in between
8
Q
bladder function?
A
storage vessel
9
Q
structure and shape of kidneys?
A
bean-shaped structures located retroperitoneally directly under the sublumbar muscles (ventrally covered with parietal peritoneum)
10
Q
what are the kidneys surrounded by?
A
by fibrous capsule
11
Q
what does each kidney lie within?
A
within a sublumbar fascia, which also holds fat (perinephric and paranephric)
12
Q
describe the lateral and medial borders of the kidneys:
A
the lateral border is strongly convex and medial is concave (nearly straight)
13
Q
describe the orientation that each kidney has?
A
each kidney has a cranial and caudal pole and a ventral and dorsal aspect
14
Q
what is the hilus of the kidney?
A
at the middle of the medial border, there is an indention - holds the renal vessels, nerves and the ureter
15
Q
difference of cows kidneys to other animals?
A
dog, cat, sheep have bean-shaped kidney whereas cow have lobated kidneys
16
Q
what veins do cat kidneys have?
A
cats have subcapsular veins
17
Q
location of kidneys in dog?
A
T13 to L3
18
Q
location of kidneys in horse?
A
T15-17 to L1
19
Q
location of kidneys in cat and dog?
A
L1 to L4
20
Q
describe location of left kidney compared to right?
A
left kidney is slightly more caudal for all except for pigs
21
Q
cranial pole of right kidney location?
A
lies in the renal fossa of the caudate liver lobe
22
Q
cranial pole of left kidney location?
A
it is adjacent to the greater curvature of the stomach and dorsomedial to the craniodorsal extremity of the spleen
23
Q
what is the parenchyma enclosed within?
A
within a tough fibrous capsule
24
Q
what is the parenchyma visibly divided into?
A
into an outer cortex and an inner medulla
25
describe the appearance of the cortex of the parenchyma?
reddish-brown colour and fine granular appearance
26
central layer of kidney - describe:
it is the medulla and has a striated look
27
in many species, how is the medulla arranged?
it is arranged as several (or even many) discrete masses, each roughly pyramidal in form
28
each medullary pyramid has what associated with it?
its associated cortex named a renal lobe
29
microscopically, the kidneys are comprised of?
nephrons, the functional unit of the kidney
30
cortex of renal lobe of kidney?
renal corpuscles and convoluted parts of renal tubules
31
what is the medulla of the kidney made up of?
collecting ducts and nephric loops
32
where are the renal papillae found?
apex of the kidney lobule
33
bovine - kidneys?
no renal pelvis - ureter divide into branches (calyx*; plural calyces)
34
pigs - kidneys?
calyx - cuplike expansion of the renal pelvis
35
renal sinus?
take kidney out and there is a gap left - filled with renal pelvis
36
blood supply of the kidneys?
renal artery
lobar artery
interlobar artery
arcuate artery
interlobular artery
afferent glomerular artery
37
sympathetic nerves to the kidneys go through?
through the celiacomesenteric plexus and along the renal arteries
38
what nerve contributes to the parasympathetic supply?
vagus nerve
39
urinary bladder?
distensible organs with no constant size, position or relationship
40
what is found dorsally to the urinary bladder?
the reproductive organs and their folds
41
what does the contracted bladder rest on?
on pubic bones
42
what is the urinary bladder confined to?
to the pelvic cavity in the larger species but extends into the abdomen of carnivores
43
larger species bladder is...
largely retroperitoneal but most of the surface becomes intraperitoneal when expanded
44
ligaments of the bladder?
three ligaments attaching urinary bladder onto the abdominal and pelvic walls
45
round ligaments of the bladder?
paired lateral vesical folds carry the round ligaments of the bladder; these are vestiges of the umbilical arteries
46
median fold of bladder?
in adult it is empty, in fetus it supports the urachus
47
urachus?
is an embryonic tube that connects the fetal bladder to the allantoic sac
48
the ligaments of the bladder?
connecting peritoneum folds
49
where does the female urethra go?
it runs caudally on the pelvic floor below the reproductive tract
50
where does the female urethra open?
open ventrally at the junction of vagina and vestibule
51
cow and sow - opening of female urethra?
opening has suburethral diverticulum - difficulties during catheterisation
52
opening of female urethra - dog?
opening is raised on a tubercle that continues somewhat over the vestibular floor
53
cat - female urethra?
cat has a groove
54
male urethra - where does it start?
starts from an internal orifice at the bladder neck to an external orifice at the free extremity of the penis
55
what is the male urethra?
it is a common track for sperm and urine
56
what parts of the male urethra are there?
pelvic and penile parts
57
pelvic part of male urethra is joined by?
joined by deferent duct and any other ejaculatory ducts
58
blood supply of the bladder - lower urinary tract?
internal iliac artery supplies the low urinary tract
59
major arterial supply of the bladder?
caudal vesical artery
60
blood supply of the bladder arises from...
from the uterine, vaginal (females) or prostatic (males) branch of the internal pudendal a.
61
bladder blood supply - cranial vesical artery?
it is the terminal ending of the umbilical artery
62
autonomic fibres - innervation of the bladder?
autonomic fibres through the sympathetic hypogastric and parasympathetic pelvic nerve
63
what fibres reach through the pudendal nerve?
sensory and motor fibres
in dogs, the pudendal nerve arises from the sacral plexus (S1, S2 and S3 spinal nerves)
64
what is the trigone of the bladder?
it is a triangle-shaped region near the junction of the urethra and the bladder
65
bladder has a?
a free apex, body and a neck
66
where is the trigone of the bladder?
internal area of the dorsal bladder between the two urethral openings (ureteric orifice) and the start of the urethra
67
what does the trigone of the bladder attach?
attaches the ureters to the bladder neck and urethra
68
what is the cranial border of the trigone formed by?
formed by longitudinal muscle fibres from each ureter crossing the midline
69
what are the lateral borders and apex are formed by?
formed by ureter longitudinal muscle fibres that continues caudally into the urethral crest
70
what does the ureter penetrate?
penetrates the bladder wall very obliquely
71
why does the ureter get compressed?
gets compressed as the intravesical pressure rises
72
what guards against reflux in ureterovesical junction?
length of the intramural course guards against reflux
73
why does the ureterovesical junction not prevent further filling of the bladder?
because the resistance is overcome by peristaltic contractions of the ureteric wall
74
for some species - what is the difference with the pyramids?
some species e.g. horses, dogs, sheep all the pyramids finally fuse to form a single medullary mass (unipyramidal or unilobar type of kidney)
75
urethral crest?
raised structure of longitudinal muscles
76
multipyramidal or multilobar (cow+pig) kidneys?
these are kidneys that retain the organisation of all the pyramids fusing to form a single medullary mass
77
pig - lobation of kidneys?
no external evidence of lobation is present
78
cow kidney lobes?
these are visible, fissures visible from the surface
79
how do urological systems deal with waste?
metabolism of protein and amino acids result in the production of nitrogen - must be excreted
80
nitrogen metabolism produces three major end products - what are these?
ammonia, urea, uric acid
81
ammonia - problem w/ nervous system?
ammonia is toxic to the nervous system and needs large amounts of water for its excretion
82
what species excrete ammonia?
aquatic species (fish, marine turtles, crocs and alligators)
83
how to deal with urea as a waste product?
most terrestrial animals don't have the option of diluting ammonia
mammals, amphibia, sharks and some reptiles such as turtles
metabolic energy must be spent to convert ammonia to urea (usually in liver)
urea is 10-100 times less toxic
84
how to deal with uric acid as waste?
other terrestrial animals, birds, and most reptiles
require even more ATP than conversion to urea
it is less toxic because highly insoluble, added benefit of removing four nitrogen per molecule and is excreted in semisolid form
Because urea is not major nitrogenous waste in birds, measure of blood urea nitrogen level cannot be used as indicators of renal function
85
what do fish use gills for?
for most excretion and retention process
86
kidneys of fish?
kidneys lie ventral to the spine and in some species sit on the swim bladder
87
what minor role do kidneys of a fish play?
in correcting salt imbalances
88
cranial section of fish kidney?
predominantly hematopoietic and lymphoid tissue
89
caudal section of fish kidney?
excretory tissue with some hematopoietic and lymphoid tissue
90
fresh water fish - ions and water compared to salt water?
fresh - saves ions and excretes more water which is the opposite for salt water fish
91
birds - kidneys?
kidneys (relatively larger than mammals) enclosed in synsacrum
92
avian nephrons?
most avian nephrons are loopless ('reptilian' type) and stay within the cortex
93
minority of nephrons in birds?
looped nephrons ('mammalian' type) extend from the cortex into the discrete medullary
94
bladder in birds?
mostly no urinary bladder
has uric acid
95
common cloaca of bird?
retro peristalsis
96
vascular system surrounding avian kidneys?
it is quite complex
97
what is the blood supply for the avian kidney?
avian kidney is supplied by three renal arteries, one for each division
98
yellow nerve on blood supply page?
schiatic nerve
99
unique feature of avian kidneys - blood supply?
the presence of an arterial and venous, or dual, afferent blood supply
100
what portal system do avian species have?
they have renal portal system (as do fish, reptiles too but not mammals)
101
what does the renal portal system function to prevent?
functions to prevent ischemic necrosis of the tubule cells during periods of water deprivation
102
arterial supply of the cranial division of the kidneys?
from a branch of the aorta, branches of the ischiatic arteries supply the middle and caudal divisions
103
a ring is formed on the ventral side of the kidneys of exotics - what is this formed by?
by the cranial and caudal portal veins which branch off the external iliac and common iliac veins
104
never inject bird in pelvic region?
it may go directly to the kidneys - may damage kidneys
105
where do cranial and caudal portal veins receive blood from?
from caudal parts of the body (through the external iliac vein) and channel it to the intralobular capillary beds that also receive arterial blood from the renal arteries
106
what do aquatic reptiles excrete? e.g. turtles
mainly excrete ammonia (possibly urea)
107
what do reptiles living in drier conditions excrete? e.g. lizards, snakes and tortoises
they excrete uric acid (uricotelic)
108
what do reptilian kidneys consist of?
they consist of nephrons without loops of henle - they cannot produce hypertonic urine - other means of water conservation must be used
109
mammals and reptiles are different considering their orifices for discharge - how?
unlike mammals, reptiles do not have separate external orifices for discharge - common cloaca
110
common cloaca?
only one opening instead of the urethra, vagina and anus
111
what is the cloaca used for?
the cloaca excretes and absorbs additional fluids and electrolytes
112
urinary bladder in reptiles?
the urinary bladder may be present and also enters (via urethra) into the cloaca
113
which reptiles have a urinary bladder?
only chelonians, the tuatara and some lizards have a urinary bladder
114
why may urinalysis not be indicative of kidney disease? - reptiles
because urine may change in bladder
115
what is the reptilian kidney also responsible for?
for VitC synthesis and conversion of VitD
116
where are kidneys located in sea turtles?
they lie in the caudal coelom, they are flattened and lobated
117
where do ureters enter in sea turtles?
ureters enter the neck of the urinary bladder, similar to mammals
118
what is the cloaca of sea turtles?
it is a common chamber
119
function of bladder of sea turtles?
serves mostly to store water and electrolytes
120
structure of bladder of sea turtles?
LARGE THIN bladder
121
bladder of sea turtles might possess what?
might possess bilateral accessory bladders on either side
122
describe the kidneys of lizards?
they are paired, symmetrical, elongated, slightly lobated and flattened dorsoventrally
123
where are most lizard kidneys located?
deep in the pelvic canal
124
what is the issue with lizard kidneys being located deep in the pelvic canal?
because disease leading to enlargement of the kidneys may cause constipation
125
do most species of lizard possess a urinary bladder?
yes
126
which lizard species possess a urinary bladder?
some species like green iguana and tortoise
127
if there is a bladder present in a lizard species, what does it not connect to?
it does not connect to ureters
128
in lizards, where does urine waste flow?
it flows from the kidney through the ureter into the cloaca, before entering the bladder (or colon for species lacking a bladder)
129
describe the difference in lizard urine compared to mammal urine:
lizard urine is non-sterile, unlike mammals
130
why is urine non-sterile in lizards?
because the urine waste flows from the kidney through the ureter INTO THE CLOACA BEFORE ENTERING THE BLADDER
131
seminal fluid?
semen
132
during the reproductive period - what can happen to the caudal segment of some lizards?
they can express sexual dimorphism during reproductive period, increasing in size to produce seminal fluid in males
133
describe the kidneys in snakes?
they are paired, flattened and elongated kidneys which contain 30-40 lobules
134
what is the SSK (sexual segment of the kidney)?
it is a hypertrophied region of the nephron
135
explain what happens to the SSK of the snake?
male snakes have sexual segment to the kidney portion of the distal tubules, "sexual segment" shows a seasonal enlargement and cellular changes
136
do snakes have a bladder?
NO
137
what do snakes have to compensate for not having a bladder?
no bladder so urine is stored either in the distal colon or distal ends of ureter
urine is then emptied into urodeum section of the cloaca and urine refluxes into the colon for fluid conservation
138
urinary excretion of a snake?
it is a thick white paste
139
do birds produce uric acid?
yes
140
what is uric acid?
it is a chemical created when the body breaks down substances called purines
141
what is blood flow to the kidneys controlled by?
by valves which are located at the junction of external iliac vein and renal vein
142
how do the valves work to control blood flow to kidneys?
it works be either directing blood to or shunting it past the kidneys as directed by the renal portal valve
143
describe what innervation the valvular smooth muscle has?
sympathetic and parasympathetic innervation
144
what is valvular smooth muscle?
it is the type of muscle that makes up most of the walls of blood vessels
145
salt glands?
most birds have extra renal structures known as 'salt' glands
146
where are salt glands located?
located dorsal to eye with ducts draining to the nose
147
what do salt glands do?
they secrete large quantities of sodium chloride which allows osmotic concentration of body fluids to be regulated
148
